It's listed in a 1960 Mt Vernon city directory:
Mt Vernon State Tuberculosis Sanitarium 601 N 18th
The University of Illinois at Chicago Library of Health Sciences has some info/records, but I'm not sure what, exactly:http://findingaids.library.uic.edu/ead/lhsc/LHS-EAD-2f.html
Also, the Mt Vernon Register newspaper has thousands of references. What exactly are you trying to find?